I would be more concerned about the sound quality characteristics of the Peachtree Nova 300 than its power ratings. Here's a quote from Art Dudley from the review mentioned previously:
"By the end of my time with Peachtree Audio's nova300, I was impressed with its superb overall musicality but remained somewhat ambivalent about its sound, at least one aspect of which—grainy trebles—is associated in the minds of some with class-D amplification in general."
I owned a Nova 300 for a while and thought it was a decent and affordable unit. That was before I owned any Thiels, so I can't comment on how it paired with them, but depending on who you listen to, it might not be a great match sonically. In regards to Art's comments above, Peachtree responded that the Nova 300 was probably not a great match with Art's high sensitivity speakers.
It's been a while since I owned mine, but my memory is more of it being a little rolled off on the top, so it might actually be a good match with the Thiels. Other integrateds that I've owned from ARC, Simaudio, and Vincent to name a few, all seemed to have a little more detail and a little more "grunt" and body than the Peachtree.